Emergence of a second SARS-CoV-2 variant with a tremendous genetic leap from its ancestors.

The on-going emergence of the Omicron BA.2.86 variant is one of the major events in SARS-CoV-2 genetic evolution that remain enigmatic regarding the overall virus mutation rate, together with the emergence of the initial Omicron variant, BA.1. Indeed, the genomes of the Omicron BA.2.86 lineage, an offspring of the second major Omicron subvariant, BA.2, harbor 39 additional mutations in the spike compared to this ancestor. Here we comment on the phylogeny of BA.2.86, on the positions, and frequencies in other SARS-CoV-2, of mutations in its spike, and on the structural model of this protein that concentrates most of BA.2.86 additional mutations.